The invention relates to a spring-loaded hinge for eyeglasses.
Spring-loaded hinges of the type mentioned here are known. They are used to improve the closing and opening behavior of eyeglass bows and to increase the flexibility and wearing comfort of the eyeglasses. Usually such hinges have at least one hinge element having a hinge eye, a locking element and at least one spring element. It is conceivable that the locking element is in engagement with the housing of the spring-loaded hinge and serves as a stop for the spring element. In this way, it is possible to house and to stop the hinge element in the housing, and thus also the hinge eye, with spring loading.
In addition, symmetrical locking elements are known for this that have, for example, two locking elements that are designed the same that can be brought into engagement with the housing. However, it has been found that the locking devices require a relatively large amount of construction space.
In order to avoid these disadvantages, an attempt was made to use locking elements with only one locking device. However, it was found in this process that because of the holding forces, these had a tendency to jam with a spring pin, which induced high bending moments in it and leads to a failure of the spring-loaded hinge during use due to jamming.
In order to avoid this, asymmetrical locks are known that have a tube-shaped recess in which the spring pin can be mounted. Finally, it has been found that in spite of the tube-shaped recess, the tendency to jam remains and a certain wear continues to occur. In addition, it has been found that additional construction space has to be provided in the longitudinal direction of the spring pin for the guide element. As a result, there is a comparably thin, but longer, spring-loaded hinge.